Alpha7 NAChR agonists are nootropic, the cholinesterase inhibitor galantamine, used for treating alzheimers, dementia etc (well not treating, merely permitting those poor accursed souls afflicted with these awful conditions to exist as something more than an ambulent, breathing cadaver for a scant handful more weeks or months) and for those seeking cognitive enhancement who are otherwise healthy, or with a non-dementia-like memory/cognitive impairment such as myself, is in addition to its AChE inhibitor properties, an alpha7 selective nicotinic receptor agonist, and seems much more effective than other cholinesterase inhibitors, I believe, due to this additional property.
I have tried both galantamine and huperzine-A (although the latter is an NMDA antagonist, although subunit-selective, I believe for NR2b-containing NMDARs, and not targeting the PCP recognition site that PCP and ket, etc go for, and likewise not targeting either the glycine or polyamine binding sites, nor acting as a pore-blocker, nevertheless this needs taking into account, I am sure, when figuring out the effects this may have on either cognitition/memory and/or opioid/stimulant etc. tolerance) and galantamine was much, much more effective for cognitive and memory enhancement.
Alpha7 nicotinic antagonists, following that line of reasoning, acting inversely, should, correspondindly, I would think, possess memory-impairing properties. I don't think this will have any effect on tolerance, but certainly I think, is likely to make it harder to remember things and think straight, causing 'brain fog' so to speak.
People who are, at baseline, not impaired in that area may not find it significant. But then again, they may. I tend to be impacted by such things, possessing cognitive/mnemonic impairing properties more than most people, as I have some rather troublesome cognitive and memory deficit issues, I believe stemming from excitotoxic damage thanks to some pretty poor decisions in my life I made several years ago, one really hideous incident involving forced, cold-turkey withdrawal from barbiturates, which I had been using to a vast excess, and several again very unpleasant withdrawals from GBL (GHB has a biphasic mode of action, being at high concentrations a GABAb receptor agonist, but it activates the GHB receptor at much lower concentrations than it does for GABAbRs, GHBr activation induces glutamate release, and selective agonists seem to be quite excitotoxic)
After all that, I am left with some memory deficit and cognitive impairment, which, while I have good and bad days, sometimes is pretty damn bad. So I tend to take into account, properties like this and their potential effects more than most people would do, or would have to.
Haven't really time to look into it right now, regarding the specific mode of action of memantine vs PCP-site noncompetitive NMDA antagonists (I.E PCP, ketamine, methoxetamine, DXM, the NMDAr antagonists most commonly used as recreational/tolerance reducing drugs) etc stuff to do, and lots of it.
Memantine is a rather odd NMDAr antagonist, with a funny mode of action at the receptor, again, I need to look into that before further posting on the subject to refresh my knowledge of it.
And thikal, I really don't think you should apologise or feel unwelcome in ADD for not being a psychopharmacology expert, I am, whilst quite the hobbyist, and autodidact in the subject, not what I could call an expert, reasonably knowledgeable and well-read, but not an employed professional, and still post here.
There are, I believe, far more commonly stupid answers, than stupid questions. Much of the time, even a poorly worded or understood question, in fact shows intelligence, the stupid wouldn't bother asking in the first place. Feel free to post here, it is how we all learn. I myself have learned quite a bit here, in ADD (amongst quite a few other places both in the subject of psychopharmacology, biochemistry and straightforward org. chem)